In many industrial applications large capacity power transistors are utilized. This requires the dissipation of heat from the transistors in order to ensure long life and reliable operation. The utilization of heat sinks without employing a cooling fluid is often inadequate.
In the prior art it is common practice to cool high-powered transistors by mounting them on a metallic chill plate. The transistor leads are passed through openings formed through the chill plate and electrical connections are made on the opposite side of the plate. Passageways are formed in the chill plate so that a cooling fluid can be circulated therethrough. Therefore, in effect, the chill plate operates as a radiator.
Since the chill plates are hooked up with fluid supplies to form fixed plumbing fixtures, testing and replacement of defective transistors requires that the transistors must be disconnected from circuit boards from which the transistor leads are connected. If a circuit board has a number of transistors connected to it and it is uncertain as to which transistor is defective, then all of the connections between the circuit board and the transistors must be disconnected to allow removal of the transistors. As will be appreciated, this is a time-consuming and often difficult procedure due to difficulty in obtaining accessibility to the circuit boards.